1. Field of the Invention
The invention relates to a generator for generating a direct voltage at a high-voltage terminal, comprising a transformer having a ferromagnetic material core, on which a primary and a secondary winding are provided, the secondary winding comprising a plurality of concentric secondary coils which are wound with the same winding senses and have substantially the same number of turns with a layer of insulating material between every two consecutive coils, the generator comprising a high voltage portion formed by a number of sections, each section comprising a portion of the secondary winding and a rectifier arranged in series with that portion, the sections being arranged in series such that all the rectifiers have the same forward directions, the last section in the arrangement being connected to the high voltage terminal.
2. Description of the Related Art
Such a generator is known from, for example, the periodical "Funkschau", 1976, Volume 24, pages 1051-1054. With this prior art generator each section of the high voltage portion is formed by a single secondary coil in series with a diode. At a given primary voltage the value of the generated direct voltage depends on the direct voltage generated per section and on the number of sections. From this it follows that for generating a high direct voltage either a large number of sections and consequently a large number of diodes are required or the number of turns per section and consequently the length of each secondary coil must be comparatively large, so that also the dimensions of the core must be large. Both increasing the number of diodes and increasing the dimensions of the core increase the cost.